Serpentine channels: micro-rheometers for fluid relaxation times
Josephine Zilz,Christof Schäfer,Christian Wagner,Robert J. Poole,Manuel A. Alves,Anke Lindner +5 more
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TLDR
In this paper, the authors propose a novel device capable of measuring relaxation times of viscoelastic fluids as small as 1 ms. In contrast to most rheometers, which by their very nature are concerned with producing viscometric or nearly-viscometric flows, here they make use of an elastic instability that occurs in the flow of vis coelastic fluid with curved streamlines.Abstract:
We propose a novel device capable of measuring relaxation times of viscoelastic fluids as small as 1 ms. In contrast to most rheometers, which by their very nature are concerned with producing viscometric or nearly-viscometric flows, here we make use of an elastic instability that occurs in the flow of viscoelastic fluids with curved streamlines. To calibrate the rheometer we combine simple scaling arguments with relaxation times obtained from first normal-stress difference data measured in a classical shear rheometer. As an additional check we also compare these relaxation times to those obtained from Zimm theory and good agreement is observed. Once calibrated, we show how the serpentine rheometer can be used to access smaller polymer concentrations and lower solvent viscosities where classical measurements become difficult or impossible to use due to inertial and/or resolution limitations. In the absence of calibration, the serpentine channel can still be a very useful comparative or index device.read more
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References
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Book
The Structure and Rheology of Complex Fluids
TL;DR: In this article, the authors present a comprehensive overview of the properties and properties of complex fluids and their properties in terms of physics, chemistry, physics theory, and physics of complex fluid properties.
Journal ArticleDOI
Drag reduction fundamentals
TL;DR: In this paper, the effects of dilute solutions of linear, random-coiling macromolecules in turbulent pipe flow is reviewed. And the experimental evidence is emphasized in three sections concerned with the graphical display of established features of the phenomenon, data correlation and analysis, and the physical mechanism of drag reduction.
Journal ArticleDOI
A purely elastic instability in Taylor-Couette flow
TL;DR: In this paper, a non-inertial (zero Taylor number) viscoelastic instability was discovered for Taylor-Couette flow of dilute polymer solutions, where the critical De was observed to increase as e decreases, in agreement with the theory.
Journal ArticleDOI
Purely elastic instabilities in viscometric flows
TL;DR: In this paper, the authors examine the growing body of knowledge surrounding how the presence of elasticity in homogeneous, flowing polymeric fluids can act in isolation to create flow bifurcation and change.